Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

$script:RepoRoot = Split-Path -Parent $PSScriptRoot
$script:ToolsRoot = Join-Path $script:RepoRoot ".tools"
$script:BinRoot = Join-Path $script:ToolsRoot "bin"
$script:GoRoot = Join-Path $script:ToolsRoot "go"
$script:GoBin = Join-Path $script:GoRoot "bin"
$script:FFmpegRoot = Join-Path $script:ToolsRoot "ffmpeg"
$script:FFmpegBin = Join-Path $script:FFmpegRoot "bin"
$script:VenvRoot = Join-Path $script:RepoRoot ".venv"
$script:VenvScripts = Join-Path $script:VenvRoot "Scripts"
$script:LocalRoot = Join-Path $script:RepoRoot ".local"
$script:GoPathRoot = Join-Path $script:LocalRoot "go"
$script:GoModCacheRoot = Join-Path $script:GoPathRoot "pkg\mod"
$script:GoBuildCacheRoot = Join-Path $script:LocalRoot "go-build-cache"
$script:CredentialFile = Join-Path $script:LocalRoot "git-credentials.psd1"

function Write-Step {
    param([string]$Message)
    Write-Host "[ai-media-hub] $Message"
}

function Invoke-CheckedCommand {
    param(
        [Parameter(Mandatory = $true)][string]$FilePath,
        [string[]]$Arguments = @()
    )

    & $FilePath @Arguments
    if ($LASTEXITCODE -ne 0) {
        $joined = if ($Arguments.Count -gt 0) { " " + ($Arguments -join " ") } else { "" }
        throw "명령 실행 실패: $FilePath$joined"
    }
}

function Ensure-Directory {
    param([Parameter(Mandatory = $true)][string]$Path)
    if (-not (Test-Path -LiteralPath $Path)) {
        New-Item -ItemType Directory -Path $Path | Out-Null
    }
}

function Get-RepoRoot { return $script:RepoRoot }
function Get-ToolsRoot { return $script:ToolsRoot }
function Get-BinRoot { return $script:BinRoot }
function Get-GoRoot { return $script:GoRoot }
function Get-GoBin { return $script:GoBin }
function Get-FFmpegBin { return $script:FFmpegBin }
function Get-VenvRoot { return $script:VenvRoot }
function Get-VenvScripts { return $script:VenvScripts }
function Get-LocalRoot { return $script:LocalRoot }
function Get-GoPathRoot { return $script:GoPathRoot }
function Get-GoModCacheRoot { return $script:GoModCacheRoot }
function Get-GoBuildCacheRoot { return $script:GoBuildCacheRoot }
function Get-CredentialFile { return $script:CredentialFile }

function Resolve-SystemCommand {
    param([Parameter(Mandatory = $true)][string]$Name)
    try {
        return (Get-Command $Name -ErrorAction Stop).Source
    } catch {
        return $null
    }
}

function Resolve-PythonExe {
    $candidates = @(
        (Join-Path $script:VenvScripts "python.exe"),
        (Resolve-SystemCommand -Name "python")
    )
    foreach ($candidate in $candidates) {
        if ($candidate -and (Test-Path -LiteralPath $candidate)) {
            return $candidate
        }
    }
    throw "python.exe를 찾을 수 없습니다. Python 3.12+가 필요합니다."
}

function Resolve-BasePythonExe {
    $all = @(Get-Command python -All -ErrorAction SilentlyContinue)
    foreach ($item in $all) {
        if ($item.Source -and $item.Source -notlike "*\.venv\*") {
            return $item.Source
        }
    }
    $fallback = Resolve-SystemCommand -Name "python"
    if ($fallback -and $fallback -notlike "*\.venv\*") {
        return $fallback
    }
    throw "시스템 python.exe를 찾지 못했습니다."
}

function Resolve-VenvPythonExe {
    $pythonExe = Join-Path $script:VenvScripts "python.exe"
    if (-not (Test-Path -LiteralPath $pythonExe)) {
        throw ".venv가 아직 준비되지 않았습니다. scripts/setup-dev.ps1를 먼저 실행하세요."
    }
    return $pythonExe
}

function Use-LocalTooling {
    Ensure-Directory -Path $script:ToolsRoot
    Ensure-Directory -Path $script:BinRoot
    Ensure-Directory -Path $script:LocalRoot
    Ensure-Directory -Path $script:GoPathRoot
    Ensure-Directory -Path $script:GoModCacheRoot
    Ensure-Directory -Path $script:GoBuildCacheRoot

    $segments = @(
        $script:BinRoot,
        $script:GoBin,
        $script:FFmpegBin,
        $script:VenvScripts,
        $env:PATH
    ) | Where-Object { $_ -and $_.Trim() -ne "" }

    $env:PATH = ($segments | Select-Object -Unique) -join ";"
    $env:GOPATH = $script:GoPathRoot
    $env:GOMODCACHE = $script:GoModCacheRoot
    $env:GOCACHE = $script:GoBuildCacheRoot
}

function Ensure-Venv {
    $venvPython = Join-Path $script:VenvScripts "python.exe"
    if (Test-Path -LiteralPath $venvPython) {
        return $venvPython
    }

    Ensure-Directory -Path $script:LocalRoot
    $pythonExe = Resolve-SystemCommand -Name "python"
    if (-not $pythonExe) {
        throw "시스템 python이 없어 .venv를 만들 수 없습니다."
    }

    Write-Step ".venv 생성"
    & $pythonExe -m venv $script:VenvRoot
    return $venvPython
}

function Install-PythonRequirements {
    param([switch]$UpgradePip)

    $venvPython = Ensure-Venv
    $systemPython = Resolve-BasePythonExe

    if ($UpgradePip) {
        Write-Step "pip 업그레이드"
        Invoke-CheckedCommand -FilePath $systemPython -Arguments @("-m", "pip", "--python", $venvPython, "install", "--upgrade", "pip")
    }

    Write-Step "worker requirements 설치"
    Invoke-CheckedCommand -FilePath $systemPython -Arguments @("-m", "pip", "--python", $venvPython, "install", "-r", (Join-Path $script:RepoRoot "worker\requirements.txt"))
}

function New-CmdShim {
    param(
        [Parameter(Mandatory = $true)][string]$Path,
        [Parameter(Mandatory = $true)][string]$Target
    )

    $content = @(
        "@echo off",
        "set SCRIPT_DIR=%~dp0",
        "`"%SCRIPT_DIR%$Target`" %*"
    ) -join "`r`n"
    Set-Content -LiteralPath $Path -Value $content -Encoding ASCII
}

function Ensure-CommandShims {
    Ensure-Directory -Path $script:BinRoot

    $pythonShimTarget = "..\..\ .venv\Scripts\python.exe".Replace(" ", "")
    New-CmdShim -Path (Join-Path $script:BinRoot "python3.cmd") -Target $pythonShimTarget

    $ytDlpExe = Join-Path $script:VenvScripts "yt-dlp.exe"
    if (Test-Path -LiteralPath $ytDlpExe) {
        New-CmdShim -Path (Join-Path $script:BinRoot "yt-dlp.cmd") -Target "..\..\ .venv\Scripts\yt-dlp.exe".Replace(" ", "")
    }
}

function Test-GoReady {
    return [bool](Resolve-SystemCommand -Name "go")
}

function Test-FFmpegReady {
    return [bool](Resolve-SystemCommand -Name "ffmpeg")
}

function Test-YtDlpReady {
    return [bool](Resolve-SystemCommand -Name "yt-dlp")
}

function Install-LocalGo {
    param(
        [string]$Version = "1.24.0",
        [string]$ArchiveUrl = ""
    )

    if (Test-Path -LiteralPath (Join-Path $script:GoBin "go.exe")) {
        Write-Step "로컬 Go 이미 준비됨"
        return
    }

    if (-not $ArchiveUrl) {
        $ArchiveUrl = "https://go.dev/dl/go$Version.windows-amd64.zip"
    }

    Ensure-Directory -Path $script:ToolsRoot
    $archivePath = Join-Path $script:LocalRoot "go-$Version.windows-amd64.zip"
    Write-Step "로컬 Go 다운로드: $ArchiveUrl"
    Invoke-WebRequest -Uri $ArchiveUrl -OutFile $archivePath

    if (Test-Path -LiteralPath $script:GoRoot) {
        Remove-Item -Recurse -Force $script:GoRoot
    }
    Expand-Archive -LiteralPath $archivePath -DestinationPath $script:ToolsRoot -Force
}

function Install-LocalFFmpeg {
    param([string]$ArchiveUrl = "https://www.gyan.dev/ffmpeg/builds/ffmpeg-release-essentials.zip")

    if (Test-Path -LiteralPath (Join-Path $script:FFmpegBin "ffmpeg.exe")) {
        Write-Step "로컬 ffmpeg 이미 준비됨"
        return
    }

    Ensure-Directory -Path $script:ToolsRoot
    $archivePath = Join-Path $script:LocalRoot "ffmpeg-release-essentials.zip"
    Write-Step "로컬 ffmpeg 다운로드: $ArchiveUrl"
    Invoke-WebRequest -Uri $ArchiveUrl -OutFile $archivePath

    $extractRoot = Join-Path $script:LocalRoot "ffmpeg-extract"
    if (Test-Path -LiteralPath $extractRoot) {
        Remove-Item -Recurse -Force $extractRoot
    }
    Expand-Archive -LiteralPath $archivePath -DestinationPath $extractRoot -Force

    $binCandidate = Get-ChildItem -Path $extractRoot -Recurse -Filter "ffmpeg.exe" | Select-Object -First 1
    if (-not $binCandidate) {
        throw "ffmpeg.exe를 압축 파일에서 찾지 못했습니다."
    }

    $sourceBin = Split-Path -Parent $binCandidate.FullName
    if (Test-Path -LiteralPath $script:FFmpegRoot) {
        Remove-Item -Recurse -Force $script:FFmpegRoot
    }
    Ensure-Directory -Path $script:FFmpegBin
    Copy-Item -Path (Join-Path $sourceBin "*") -Destination $script:FFmpegBin -Recurse -Force
}

function Get-AppEnvironment {
    param(
        [Parameter(Mandatory = $true)][string]$WorkspaceRoot,
        [Parameter(Mandatory = $true)][string]$DownloadsDir,
        [Parameter(Mandatory = $true)][string]$SqlitePath,
        [Parameter(Mandatory = $true)][string]$AppAddr,
        [string]$SearxUrl = "http://127.0.0.1:18080"
    )

    return @{
        APP_ROOT                  = $WorkspaceRoot
        APP_ADDR                  = $AppAddr
        SQLITE_PATH               = $SqlitePath
        DOWNLOADS_DIR             = $DownloadsDir
        FRONTEND_DIR              = (Join-Path $WorkspaceRoot "frontend")
        WORKER_SCRIPT             = (Join-Path $WorkspaceRoot "worker\downloader.py")
        SEARXNG_BASE_URL          = $SearxUrl
        SEARXNG_GOOGLE_VIDEO_ENGINE = "google videos"
        SEARXNG_WEB_ENGINE        = "google"
    }
}

function Import-GitCredential {
    $credentialFile = Get-CredentialFile
    if (-not (Test-Path -LiteralPath $credentialFile)) {
        throw "git 자격정보 파일이 없습니다: $credentialFile"
    }
    return Import-PowerShellDataFile -Path $credentialFile
}